(a) Field of the Invention
The present invention relates to a display device and a driving method thereof. More particularly, the present invention relates to a display device with reduced power consumption and that prevents deterioration of visibility, changes in luminance, and perceptibility of flicker, and a driving method thereof.
(b) Description of the Related Art
Currently, display devices are required for devices such as computer monitors, televisions, mobile phones, and the like, which are widely used. The various types of display devices include cathode ray tube display devices, liquid crystal displays, plasma display devices, and the like.
A display device includes a graphics processing unit (GPU), a display panel, and a signal controller. The graphics processing unit transmits image data of a screen to be displayed on the display panel to the signal controller. The signal controller then generates a control signal for driving the display panel to transmit the control signal together with the image data to the display panel, thereby driving the display device.
Images displayed on the display panel are broadly classified into still images and motion pictures. The display panel is capable of displaying several frames per second, and if the image data included in the frames are identical, a still image is displayed. Conversely, if the image data included in the frames are different, a motion picture is displayed.
In this case, because the signal controller receives the same image data from the graphics processing unit for every frame regardless of whether the display panel displays a motion picture or a still image, power consumption increases.
Recently, many methods for reducing power consumption of display devices have been researched. Among these, is a method in which a frame memory is added to the signal controller, and the image data of the still image is stored in a frame memory. The storage image data is provided to the display panel while displaying the still image. The method is called a pixel self-refresh (PSR) mode. Because the image data does not need to be received from the graphics processing unit while displaying the still image, the graphics processing unit may be deactivated to reduce power consumption.
When being driven in the PSR mode, however, the addition of the frame memory introduces a problem of increased power consumption.
The above information disclosed in this Background section is only for enhancement of understanding of the background and therefore it may contain information that does not form the prior art that is already known to a person of ordinary skill in the art.